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Message-ID: <3b7c068b-ac7e-62fc-f0cd-a8dbf8642876@redhat.com>
Date:   Mon, 28 Feb 2022 10:37:46 +0100
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Subject: Re: [PATCH V3] selftests: vm: Add test for Soft-Dirty PTE bit
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To:     Muhammad Usama Anjum <usama.anjum@collabora.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Shuah Khan <shuah@kernel.org>
Cc:     kernel@collabora.com, kernelci@groups.io,
        Will Deacon <will@kernel.org>,
        Gabriel Krisman Bertazi <krisman@collabora.com>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        linux-kselftest@vger.kernel.org
References: <20220224212335.3045905-1-usama.anjum@collabora.com>
From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
In-Reply-To: <20220224212335.3045905-1-usama.anjum@collabora.com>
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On 24.02.22 22:23, Muhammad Usama Anjum wrote:
> This introduces three tests:
> 1) Sanity check soft dirty basic semantics: allocate area, clean, dirty,
> check if the SD bit flipped.
> 2) Check VMA reuse: validate the VM_SOFTDIRTY usage
> 3) Check soft-dirty on huge pages
> 
> This was motivated by Will Deacon's fix commit 912efa17e512 ("mm: proc:
> Invalidate TLB after clearing soft-dirty page state"). I was tracking the
> same issue that he fixed, and this test would have caught it.
> 

A note that madv_populate.c already contains some SOFTDIRTY tests
regarding MADV_POPULATE. Eventually we want to factor out
softdirty/pagemap handling+checks for easier reuse.


-- 
Thanks,

David / dhildenb